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E39 (1997 - 2003) The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

I went into the shopping center for about twenty minutes, upon returning to my car I noticed fog on the inside windshield, once I opened the door I heard the blower motor going. I woke up the next morning and my battery was completely dead. I didn't know it until today but I have had FSU issues since last summer. The a/c would just cut off and no matter the setting it wouldn't come back on until it wanted to, I never thought to look it up as the a/c would always start to blow again before the end of my trip. Know on to the question, Have we gathered more info on the best FSU to purchase someone point me in the right direction or should I just go to my dealer?

I went into the shopping center for about twenty minutes, upon returning to my car I noticed fog on the inside windshield, once I opened the door I heard the blower motor going. I woke up the next morning and my battery was completely dead. I didn't know it until today but I have had FSU issues since last summer. The a/c would just cut off and no matter the setting it wouldn't come back on until it wanted to, I never thought to look it up as the a/c would always start to blow again before the end of my trip. Know on to the question, Have we gathered more info on the best FSU to purchase someone point me in the right direction or should I just go to my dealer?

A Behr FSU from Autohaus or another supplier is $52. Putting aside where Behr makes their FSU, I'm pretty sure the replacement part that the stealer sells is over $100...someone can look it up, or I can check, I'll be at the stealer tomorrow.

Unless BMW has switched to Bosch for the replacement part for some reason, then Behr is/should be sufficient. If my new one fails, I guess I will replace it with whatever the stealer sells.

I have some new information, via the parts counter at the stealer. I asked to see the FSU, using Starless's part #. He brought out an FSU with an aluminum housing, which looks exactly like the one Starless used. Then, after asking exactly what car it was for, he said that was the "old one" and brought out the correct one, which looks EXACTLY like the one I bought from AutohausAZ, except (wait for it) it was labeled Sitronic/Valeo, made in Germany. The cost was $116 (versus the $52 I paid). It shares the part # that is in the image I posted from AutohausAZ. He noted that all their electronics are made in Germany, and that any Web site/supplier can claim OEM if the part will work. He said the part THEY use was never made by Behr. Uh oh.

He brought out an FSU with an aluminum housing, which looks exactly like the one Starless used

That was a "Behr/Hella", made in Germany (based on photos above).

Quote:

Originally Posted by Josh P.

brought out the correct one, which looks EXACTLY like the one I bought from AutohausAZ, except (wait for it) it was labeled Sitronic/Valeo, made in Germany.

Yours from AutoHauz was a Behr/Hella, made in China.
Your stealer's is Sitronic/Valeo/BMW, made in Germany.

Quote:

Originally Posted by Josh P.

He said the part THEY use was never made by Behr. Uh oh.

It's really hard to tell who 'made' these things ... because of the multiple labeling - and - apparently, they no longer stamp the 'real' manufacturer on the housing (right?), so, I, for one, am having trouble concluding much of anything different from the first post of this thread.

Can someone summarize the general conclusion so far as to which is the 'good' brand and origin?

If you're the belt and suspenders type, just suck it up and buy it from BMW. I am OK using Autohaus's unit for now. If it fails, hopefully they will take it back. If they don't, then I'll be out 52 bucks and I'll just buy the stealer's. All I know is they look exactly the same. Naturally I don't know what's inside, but it's hard to believe it's not the same circuitry, since it has to do the same things.

A pic of my old FSU. Touched the FSU after about 6 hours after shutting her down and the FSU was very very warm also my battery died as a result of this test. So I will be ordering a new FSU from Josh.P source. My original has what seems to me like a date code stamped on the plastic sticker, it reads 12 / 02, but the molding has 01? it also has the BMW GKR Valeo markings. GKR is also stamped into the molding. It is the old style 12 prong version.
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Hi guys, i have been following this thead for a while and would like to contribute with my findings. Long story short my car was dead every morning but my AC controls worked fine. I suspected the FSU from researching the problem, prior to finding this thread i ordered a FSU from ebay.

Ebay FSU
Part Brand: Hamburg Technic Germany
Manufacturer Part Number: 64 11 6 923 204 / 64116923204
Got the FSU and installed, solved my battery drain for 4 days then the drain returned. Stay away from this POS, i should of known better for the price but he had good feeback so i gave it the benefit of the doubt.

Ordered another FSU but this time from Mark @ EACTUNING
On the catalog they had the BEHR and "OEM BMW" i went for the OEM BMW one that costed $67 vs the BEHR at $61. I was hoping that the OEM was the Sitronic one and i just want to confirm that its the one i received and i installed and so far no battery drain. So if anybody wants the Sitronic one you can get from him at a great price.

Concurring with the fact that ACM isn't on our list (yet) of known FSU suppliers, to my knowledge, only two posters have admitted to owning ACM FSUs (one of them is little old me).

The ACM company, if my googling hit the right ACM, appears to be a wholly owned subsidiary of FABENTI GmbH (Ltd.), where ACM apparently had it origins in Italy, full name "automotive climate-control marketing GmbH" (sic).

images are of the old one, started to try and repair, but my wife got impatient and wanted to go somewhere so i gave up
will try to add pics of the new one if i get a minute to take it back out ( didnt think to take pics before i put it in, did it in the napa parking lot)

Here's what I got today from BMAParts.com for $60 shipped. I'll update which part failed on mine... I'm assuming it's original. my car is a 2002 330i @ 111k miles. It's been acting up for the past six months but yesterday shut down the air altogether then magically started working again 10 minutes later. I don't want to chance a battery drain so I ordered this up!

I apologize if this was covered. I did not read this thread carefully, but me fan motor stopped working abruptly. I assumed it was the FSU. I ordered one and went to install it. No go. So I found this post and did this test to see if the fan Motor was broken:

came back from chicago area dealer looking at part it matched first post with siltronic and valeo marked on it. price was $115 so still looking better price. I've had car since new (2000 model year 67k miles)and under warrantee had the fsu replaced but never saw part. 2nd part is starting to act up on occasion some weeks no problems

came back from chicago area dealer looking at part it matched first post with siltronic and valeo marked on it. price was $115 so still looking better price. I've had car since new (2000 model year 67k miles)and under warrantee had the fsu replaced but never saw part. 2nd part is starting to act up on occasion some weeks no problems

Did we ever, tribally, come to a conclusion yet on which 'brand' of FSU to buy?

As with most things regarding these cars, there are few, if any absolutes. There is a LOT of variability in FSU quality.
I think if you have any doubts regarding FSU quality (and there is a lot of evidence to give doubt), go to the dealer, pay the premium, and install OEM (I paid about $90 at the stealer). If the cost of maintaining your E39 is starting to chafe on you, get an alternative lower cost FSU from a reputable source and roll the dice. Bottom line is that installation is an easy 10 min DIY (~$100 at the stealer) so there is minimal labor investment. If it craps out, buy another and reinstall it. If it lasts, you've saved $30-$40. If it doesn't, you're only out about $10-$30.